We: 1) cloned, sequenced and functionally identified the rat and human vesicular acetylcholine transporters (VAChTs), 2) determined the distribution of vesicular acetylcholine abd vesicular monoamine transporters (VMATs) in neurons and endocrine cells, 3) identified a mammalian gene locus responsible for co-expressing VAChTs an choline acetyltransferase (ChAT), 4) demonstrated that the gene encoding the neuropeptide vasoactive intestinal polypeptide (VIP) is positively regulated via tow discrete cis-acting elements in a neuroendocrine cell- specific manner, while the VAChT/ChAT gene appear to be expressed via a de-repression mechanism in cholinergic cells, 5) demonstrated sorting of VAChT and VMAT1 to small synaptic vesicles (SSVs) and large dense-core vesicles (LDCVs) respectively, by immune electron microscopy and 5) obtained preliminary evidence for a role of chromogranin A in gemeraton of the LDCVs by identifying LDCV-like structures in non-endocrine cells programmed to express chromogranin A.